The red blood cell (RBC) transfusion "trigger" has been used to refer to the minimum hemoglobin (Hb) of hematocrit (Hct) values or the clinical sign or symptom at which a RBC transfusion should administered. The RBC transfusion triggers involving clinical signs or symptoms in anemic neonates and apnea. Because RBC transfusions are expensive and are not without risk, the development of accurate and sensitive triggers is needed to improve clinical decisions regarding the need to transfuse. The purpose of this research is to determine the potential utility of using auditory brainstem responses neonates. These electrophysiologic tests objectively examine the integrity of the auditory nervous system and therefore may be sensitive to any anemic changes that impair its normal function. The experimental protocol includes an examination of both an animal and human model. Sheep were chosen as the experimental because of their extensive use in perinatal and development physiology for both sheep and pre-term neonates along with the corresponding ABR and DPE recordings. A correlation between different degrees of anemia and any changes in ABRs and DPEs, which may reflect auditory nervous system impair, will be examined.